Specific Antipredator Response of Leopard Geckos (Eublepharis macularius) to the Smell of Snake Exuvia
Abstrakt
This study aimed to establish a new bioassay for the chemosensory discrimination of snake predators by leopard geckos, Eublepharis macularius. It quantifed tongue ficking and antipredator behaviour of leopard geckos using several tests analysing reactions to: (1) exuviae from six snake predators selected in terms of gecko predation, (2) intact exuviae against exuviae extracted with polar and non-polar solvents, and (3) exuviae against various scentless and scented control stimuli.
We found that geckos discriminate the odour of snake exuviae against controls: snake exuviae trigger antipredator responses that take the form of either active (high postures, attacks) or passive (low postures, avoidance, and escape) antipredator reactions. Geckos reacted to the odour of all snake exuviae but with variations in form and intensity between snake species. Geckos reacted to exuviae after odour removal by a polar solvent, but the reaction was abolished after non-polar solvent application.
Tongue ficking appeared to be indiscriminate although it may refect the animal's interest towards unfamiliar stimuli. Finally, the geckos' antipredator reactions to snake exuviae were comparable to those elicited by live snakes. This study validates a new bioassay for predator scents in geckos.